Melt-blown fiber web with improved concentration force and elasticity and method and apparatus for manufacturing the same

ABSTRACT

Disclosed is a melt-blown fiber web with improved concentration force and elasticity, whereby a melt-blown fabric is cut and sealed at predetermined intervals using knives having arbitrary patterns so that concentration force and elasticity of the melt-blown fiber web can be improved without degrading the inherent function of the fiber web. Further disclosed are a method and apparatus for manufacturing the melt-blown fiber web. The melt-blown fiber web includes thermoplastic filaments, wherein cutting portions and sealing portions are arranged on top and bottom surfaces of the fiber web at predetermined intervals along a thickness of the fiber web so that a concentration force and elasticity of the fiber web are improved.

CROSS-REFERENCE TO RELATED PATENT APPLICATION

This application claims the benefit of Korean Patent Application No.10-2012-0125856, filed on Nov. 8, 2012 in the Korean IntellectualProperty Office, the disclosure of which is incorporated herein in itsentirety by reference.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The present invention relates to a melt-blown fiber web with improvedconcentration force and elasticity and a method and apparatus formanufacturing the melt-blown fiber web.

2. Description of the Related Art

In general, a process of manufacturing a melt-blown fiber web includes awave forming process in which filaments are extended and are formed intoa wave by spraying a thermoplastic resin, such as polypropylene, ontothe filaments in a vertical downward direction so as to allow ahigh-temperature and high-speed gas having constant temperature,pressure, and speed to collide with the filaments. The process furtherincludes collecting and stacking the filaments in which the wave isformed to thereby form the fiber web.

Since melt-blown fine fibers that are manufactured in the above processhave a very thin average diameter of about 0.3 to 10 μm, together with avery large surface area, the melt-blown fine fibers are widely used forvarious types of high-performance filters, wipers, oil-absorbingmaterials, heat insulation materials, and absorbers.

However, since the fine fibers that form the melt-blown fiber web have alow strength and a weak concentration force between the fine fibers,when the melt-blown fiber web is used without performing additionalprocessing, the concentration of the fiber web may be easily destroyed.

In order to reinforce the strength of the fine fibers and theconcentration force between the fine fibers, the melt-blown fiber web issubjected to additional processing prior to use.

For example, the strength of the fine fibers and the concentration forcebetween the fine fibers can be reinforced by connecting arbitraryportions of the melt-blown fiber web using a high frequency treatingdevice, or by sewing and fixing the melt-blown fibers.

However, when exiting methods are used, costs increase. Further, thefiber web becomes damaged when high frequency treatment or sewing isperformed. Thus, the inherent function of the fiber web may be degraded,or the thickness of the fiber web may be very small.

SUMMARY OF THE INVENTION

The present invention provides a melt-blown fiber web with improvedconcentration force and elasticity. More particularly, the presentinvention provides a melt-blown fabric that is cut and sealed atpredetermined intervals using knives having arbitrary patterns so thatconcentration force and elasticity of the melt-blown fiber web can beimproved without degrading the inherent function of the fiber web. Thepresent invention further provides a method and apparatus formanufacturing the melt-blown fiber web.

According to an aspect of the present invention, there is provided amelt-blown fiber web including thermoplastic filaments, wherein cuttingportions and sealing portions are arranged on top and bottom surfaces ofthe fiber web at predetermined intervals along a thickness of the fiberweb so that a concentration force and elasticity of the fiber web areimproved.

According to various embodiments, the shape of each of the cuttingportions and the sealing portions is at least one selected from thegroup consisting of a straight line shape, a cross shape, an X-shape, acircle, and a T-shape, or a combination thereof.

According to another aspect of the present invention, there is provideda method of manufacturing a melt-blown fiber web, the method including:manufacturing a melt-blown fiber web by melting, extruding, andradiating a thermoplastic resin composite, wherein a high-temperatureand high-speed gas is allowed to collide with filaments simultaneouslywith radiation; forming cutting portions and sealing portions inpredetermined patterns at predetermined intervals by applying a shearingforce to a surface of the manufactured melt-blown fiber web using knivesand by fusing the melt-blown fiber web by heat; and winding themelt-blown fiber web in which the cutting portions and the sealingportions are formed.

According to another aspect of the present invention, there is providedan apparatus for manufacturing a melt-blown fiber web using athermoplastic resin, the melt-blown fiber web having improvedconcentration force and elasticity, the apparatus including: an unwinderthat unwinds a predetermined amount of wound melt-blown fiber web; atransfer unit that transfers the unwound melt-blown fiber web; a cuttingand sealing unit that cuts and fuses a surface of the transferredmelt-blown fiber web in predetermined patterns; and a winding roll thatwinds the melt-blown fiber web.

According to various embodiments, the cutting and sealing unit includesa rolling roll that has knives having a predetermined shape that arearranged on an outer circumferential surface of the cutting and sealingunit at predetermined intervals. Preferably, such a cutting and sealingunit pressurizes the surface of the melt-blown fiber web atpredetermined intervals by rotating the knives so that the melt-blownfiber web is cut and sealed.

According to various embodiments, the cutting and sealing unit includesa press mold that has knives having a predetermined shape arranged on abottom surface of the cutting and sealing unit at predeterminedintervals. Preferably, such a cutting and sealing unit pressurizes thesurface of the melt-blown fiber web at predetermined intervals byvertically moving the knives so that the melt-blown fiber web is cut andsealed.

According to various embodiments, the cutting and sealing unit includesa press mold that has knives having a predetermined shape arranged on abottom surface of the cutting and sealing unit at predeterminedintervals. Preferably, such a cutting and sealing unit vertically movesthe knives, and pressurizes the surface of the melt-blown fiber web atpredetermined intervals using a steel plate as a support plate so thatthe melt-blown fiber web is cut and sealed.

According to various embodiments, when cutting portions and sealingportions are formed on the melt-blown fiber web using the knives, thesealing portions are completely cut and sealed by a shearing force ofthe knives. In particular, the sealing portions may be cut according toa thickness of a blade of each of the knives. Alternatively, the sealingportions may be cut with a minimum thickness of about 0.16 to 0.2 mm dueto pressure of the knives. After cutting, the sealing portions aresealed.

Other aspects and exemplary embodiments of the invention are discussedinfra.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other features and advantages of the present inventionwill become more apparent by describing in detail exemplary embodimentsthereof with reference to the attached drawings in which:

FIG. 1 is a flowchart illustrating a method of manufacturing amelt-blown fiber web according to an embodiment of the presentinvention;

FIG. 2 is a side view of an apparatus for manufacturing a melt-blownfiber web according to an embodiment of the present invention;

FIG. 3A is a side view of an apparatus for manufacturing a melt-blownfiber web according to another embodiment of the present invention;

FIG. 3B is a side view of apparatus for manufacturing a melt-blown fiberweb according to another embodiment of the present invention;

FIG. 4 is a plan view of a rolling roll of a device for cutting andsealing a melt-blown fiber web of the apparatus illustrated in FIG. 2;

FIG. 5A is a plan view and a cross-sectional view of a melt-blown fiberweb according to an embodiment of the present invention;

FIG. 5B is a plan view and a cross-sectional view of a melt-blown fiberweb according to another embodiment of the present invention;

FIG. 6 is a plan view of a melt-blown fiber web that is cut inpredetermined patterns, according to an embodiment of the presentinvention;

FIG. 7 is a schematic view of various patterns of cutting and sealingknives according to an embodiment of the present invention; and

FIG. 8 is a graph showing the result of testing absorption performanceof a melt-blown fiber web according to the present invention andabsorption performance of a melt-blown fiber web according to therelated art.

It should be understood that the appended drawings are not necessarilyto scale, presenting a somewhat simplified representation of variouspreferred features illustrative of the basic principles of theinvention. The specific design features of the present invention asdisclosed herein, including, for example, specific dimensions,orientations, locations, and shapes will be determined in part by theparticular intended application and use environment.

In the figures, reference numbers refer to the same or equivalent partsof the present invention throughout the several figures of the drawing.

DETAILED DESCRIPTION OF THE INVENTION

The present invention will now be described more fully with reference tothe accompanying drawings, in which exemplary embodiments of theinvention are shown, so that one of ordinary skill in the art can easilyembody the present invention.

The term “thermoplastic resin” as used in the present specificationrefers to a resin in which a process of applying heat with a highertemperature than a melting point to a polymer resin, melting, cooling,and solidifying the polymer resin can be repeatedly performed.

The thermoplastic resin may be classified into a crystallinethermoplastic resin and an amorphous thermoplastic resin according to adegree of crystallinity of the polymer. The crystalline thermoplasticresin includes polyethylene, polypropylene, and nylon, and the amorphousthermoplastic resin includes polyvinyl chloride, and polystyrene.

The term “polyolefin” as used herein refers to hydrocarbon polymers witha saturated open chain including carbon and hydrogen. Generalpolyolefins include various mixtures of polyethylene, polypropylene,polymethylene and ethylene, or propylene and methlypentene monomer.

The term “polypropylene (PP)” as used herein refers to single polymer ofpropylene or a copolymer that is the unit of propylene with a 40% ormore repetition unit.

The term “polyester” as used herein refers to polymer that is connectedby formation of an ester unit and is a condensation product ofdicarboxylic acid and dihydroxy alcohol with a 85 % or more repetitionunit. This includes aromatic, aliphatic, saturated and unsaturateddiacid and di-alcohol. The term “polyester” as used herein furtherrefers to copolymer, a blend, or a modified product thereof. A generalexample of a polyester is polyethylene terephthalate (PET), which is acondensation product of ethylene glycol and terephthalic acid.

The terms “melt-blown fiber” and “melt-blown filament” as used hereinrefers to a fiber or filament that is formed by extruding a moltenporous polymer together with a high-temperature and high-speedcompressed gas through a plurality of fine capillary tubes.

Here, the capillary tubes may be modified in various ways, such as atube having a circular cross-section, a tube having a polygonal(triangular or rectangular) cross-section, or a tube having an asteriskshaped cross-section. Also, for example, the high-temperature andhigh-speed compressed gas may be used to cause a filament formed ofmolten thermoplastic copolymer to be thin, and may, for example, reducea diameter of the filament to about 0.3 to 10 μm. The melt-blown fibermay be a discontinuous or continuous fiber.

The term “spunbond” as used herein refers to a fiber web that ismanufactured by extending a plurality of filaments having a finediameter that are extruded through capillary tubes by using ahigh-temperature tube. The spunbond fiber is continuous in a lengthwisedirection of the filament, and the average diameter of the plurality offilaments is larger than about 5 μm. A spunbond nonwoven product ornonwoven web is formed by irregularly arranging spunbonds on acollection surface, such as a porous screen or belt.

The terms “nonwoven product, fiber web, and nonwoven web” as used hereinrefer to a structure including individual fibers, filaments, or threadsthat form a planar material by arranging the individual fibers,filaments, or threads in an irregular manner without patterns. Such astructure is in contrast to a knitted product.

It is understood that the term “vehicle” or “vehicular” or other similarterm as used herein is inclusive of motor vehicles in general such aspassenger automobiles including sports utility vehicles (SUV), buses,trucks, various commercial vehicles, watercraft including a variety ofboats and ships, aircraft, and the like, and includes hybrid vehicles,electric vehicles, plug-in hybrid electric vehicles, hydrogen-poweredvehicles and other alternative fuel vehicles (e.g., fuels derived fromresources other than petroleum). As referred to herein, a hybrid vehicleis a vehicle that has two or more sources of power, for example bothgasoline-powered and electric-powered vehicles.

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting of the invention. Asused herein, the singular forms “a,” “an” and “the” are intended toinclude the plural forms as well, unless the context clearly indicatesotherwise. It will be further understood that the terms “comprises”and/or “comprising,” when used in this specification, specify thepresence of stated features, integers, steps, operations, elements,and/or components, but do not preclude the presence or addition of oneor more other features, integers, steps, operations, elements,components, and/or groups thereof. As used herein, the term “and/or”includes any and all combinations of one or more of the associatedlisted items.

Unless specifically stated or obvious from context, as used herein, theterm “about” is understood as within a range of normal tolerance in theart, for example within 2 standard deviations of the mean. “About” canbe understood as within 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, 0.5%,0.1%, 0.05%, or 0.01% of the stated value. Unless otherwise clear fromthe context, all numerical values provided herein are modified by theterm “about”.

Hereinafter, exemplary embodiments of the present invention will bedescribed in detail with reference to the accompanying drawings.

FIG. 1 is a flowchart illustrating a method of manufacturing amelt-blown fiber web according to an embodiment of the presentinvention, FIG. 2 is a side view of an apparatus for manufacturing amelt-blown fiber web according to an embodiment of the presentinvention, and FIG. 4 is a plan view of a rolling roll 14 of a devicefor cutting and sealing a melt-blown fiber web of the apparatusillustrated in FIG. 2.

First, filaments are made to have a small diameter of about 0.3 to 10 μmby melting, extruding, and radiating a thermoplastic resin compositethrough a filament radiation tube. Further, a high-temperature andhigh-speed gas is caused to collide with the radiated filamentssimultaneously with radiation, thereby manufacturing a melt-blown fiberweb 1.

The melt-blown fiber web 1 may be manufactured generally by a method andapparatus for manufacturing a melt-blown fiber web disclosed in KoreanPatent Laid-open Publication No. 2011-0122566 filed by the presentapplicant.

According to the present invention, a concentration force and elasticityof the melt-blown fiber web 1 is reinforced by cutting and sealingportions of the melt-blown fiber web 1. In particular, according tovarious embodiments, portions are cut and sealed by pressurizing knives14 b having a predetermined shape. As such, the pressurizing knives 14 bcome into contact with the melt-blown fiber web 1 manufactured using theabove method in predetermined patterns.

A process of cutting and sealing the surface of the melt-blown fiber web1 is performed after the melt-blown fiber web 1 has been formed andbefore the fiber web 1 of a final product is wound. Preferably thecutting and sealing are simultaneously performed.

According to an embodiment of the present invention, a device forcutting and sealing the surface of the melt-blown fiber web 1 includesan unwinder 10 that unwinds the wound melt-blown fiber web 1 at apredetermined speed, a transfer unit 13 that transfers the fiber web 1that has been unwound by the unwinder 10 to a cutting and sealing unit15, and a cutting and sealing unit 15 that cuts and seals the fiber web1 that has been transferred by the transfer unit 13. The device forcutting and sealing the surface of the melt-blown fiber web 1 having theabove structure may be disposed inline with an existing apparatus formanufacturing a melt-blown fiber web. As such, the cutting and sealingdevice may manufacture the fiber web 1 continuously.

According to various embodiments, the unwinder 10 is a device forsupplying the melt-blown fiber web 1, which preferably has a diameter of0.3-10 μm and is formed in the above step, to the cutting and sealingunit 15. The unwinder 10 may be configured and arranged to unwind thefiber web 1 by rotation from a cylindrical roll on which the melt-blownfiber web 1 is wound.

As shown in the embodiment of FIG. 2, the transfer unit 13 can have twotransfer rollers 11 that are connected to a belt 12, such as a conveyorbelt. The two transfer rollers 11 can be rotated by a driving unit, suchas a motor, based on the speed of the unwinder 10 to transfer themelt-blown fiber web 1 mounted on the conveyor belt 12 continuously in ahorizontal direction.

The cutting and sealing unit 15 as shown in the embodiment of FIG. 2,can include the rolling roll 14, which is disposed over the fiber web 1,and support and transfer rollers 17 that are disposed under the fiberweb 1 at predetermined intervals in the horizontal direction.

The rolling roll 14 and the support and transfer rollers 17 are disposedrelative to each other to provide a predetermined gap in a verticaldirection therebetween through which the fiber web 1 passes.

As shown in FIG. 2, the rolling roll 14 may include a cylindrical rollbody 14 a, and knives 14 b or other forms of sharpened projections(hereinafter generally referred to as knives) disposed on an outercircumferential surface of the roll body 14 a at predeterminedintervals, for example as illustrated in FIG. 4.

As illustrated in FIG. 4, the rolling roll 14 may be coupled in a hingedstructure by a rotation shaft 14 c, which is formed integrally with bothends of the rolling roll 14 and protrudes therefrom. The rotation shaftmay be connected to a motor or the like so as to rotate the rolling roll14 using a driving force of the motor.

The knives 14 b may protrude from the outer circumferential surface ofthe roll body 14 a of the rolling roll 14 at predetermined intervals ina lengthwise direction and a circumferential direction and may cut andseal the melt-blown fiber web 1 in predetermined patterns, for example,by vertically pressurizing the surface of the fiber web 1 as it istransferred in the horizontal direction.

FIG. 7 is a schematic view of various patterns that may be made by thecutting and sealing knives 14 b according to embodiments of the presentinvention. As shown, the knives 14 b may be straight-line shaped (−),cross-shaped (+), x-shaped (X), a circle in which a hole is formed in adirection of a diameter of the knives 14 b (∘), or

-shaped, for example.

In this case, the cross-section of the knives 14 b that contact thefiber web 1 may be minimized so as to minimize the damage of the fiberweb 1.

A method of forming predetermined patterns on the surface of themelt-blown fiber web 1 having the above structure will be describedbelow. When the fiber web 1 is allowed to pass through a space betweenthe rolling roll 14 rotated by the motor and the support and transferrollers 17, the knives 14 b disposed on the outer circumferentialsurface of the rolling roll 14 apply a shearing force onto the surfaceof the fiber web 1. Due to characteristics of a thermoplastic resin usedas a material for the melt-blown fiber web 1, when the shearing force isapplied to the thermoplastic resin, heat is generated, and a top surfaceof the fiber web 1 is widened by the thickness of the knives 14 b due tothe shearing force and heat and is cut and simultaneously, a bottomsurface of the fiber web 1 is sealed.

In this way, when cutting and sealing are performed using the shearingforce of the knives 14 b, patterns with a predetermined interval, suchas a stitch mark, remain on the surface of the fiber web 1. In thismanner, the cutting and sealing method using the knives 14 b usesadditional equipment, such as an existing high frequency treatingdevice, or fixes the melt-blown fiber web 1 by using an adhesive or bysewing using threads, which is fundamentally different from reinforcingthe concentration force of the fiber web 1. By mechanically rotating thesharp knives 14 b to apply the shearing force to the thermoplasticresin, cutting and sealing are performed without degrading the inherentfunction of the fiber web 1. AS such, the concentration strength of thefiber web 1 can be easily reinforced.

In other words, the contact and pressurized area of the knives 14 b andthe fiber web 1 is minimized compared to an existing sewing process. Asa result, damage to the fiber web 1 by pressurization is minimized, theconventional problem related to a very small thickness of the fiber web1 is solved to thereby maintain the inherent function of the fiber web1, the top surface of the fiber web 1 is somewhat widened, and thebottom surface of the fiber web 1 is fused by heat so that the fiber web1 is provided with increased concentration strength and elasticity.

Here, the melt-blown fiber web 1 may be cut and sealed using heat thatis naturally generated when it is cut by the knives 14 b. Alternatively,the knives 14 b may be heated at a predetermined temperature to providefor cutting and sealing.

For example, in order to heat the knives 14 b, the rolling roll 14 andthe knives 14 b may be heated using a heater mounted in the rolling roll14.

As described above, when the fiber web 1 is cut and sealed by heatprovided by the knives 14 b, the concentration strength of the fiber web1 can be maximized.

FIG. 3A is a side view of an apparatus for manufacturing the melt-blownfiber web 1 according to another embodiment of the present invention. Asshown, the cutting and sealing unit 25 may be in the form of a pressmold 24 that has a bottom surface on which knives 24 b or other forms ofsharpened projections (hereinafter generally referred to as knives) aremounted, and that is movable in a vertical direction.

According to an exemplary embodiment, the vertical movement of the pressmold 24 is guided by guide bars 26 vertically disposed at corners of thepress mold 24, and the press mold 24 is vertically driven by a hydraulicor pneumatic cylinder mechanism.

Again, the shape of the knives 24 b may vary, as described above.

FIG. 3B is a side view of an apparatus for manufacturing the melt-blownfiber web 1 having a similar configuration as that in FIG. 3A, accordingto another embodiment of the present invention. A method of operatingthe apparatus of FIG. 3B is the same as or similar to the apparatus ofFIG. 3A. As shown in FIG. 3B, the apparatus may be driven using a steelplate 37 as a support plate of knives 34 b of a press mold 34.

Again, the shape of the knives 34 b may vary, as described above.

FIG. 5A is a plan view and a cross-sectional view of a melt-blown fiberweb 1 according to an embodiment of the present invention. Referring toFIG. 5A, patterns having the same shape as straight-line shaped orcross-shaped knives 14 b, 24 b, and 34 b are formed on the melt-blownfiber web 1 using cutting and sealing units 15, 25, and 35.

Next, the melt-blown fiber web 1 in which cutting portions 2 a and 2 a′and sealing portions 2 b and 2 b′ with predetermined patterns are formedin the cutting and sealing process, is wound on a winding roll 16.

Here, the shape of the sealing portions 2 b and 2 b′ may vary accordingto the thickness of a blade of the straight-line shaped or cross-shapedknives 14 b, 24 b, and 34 b.

For example, if the thickness of a blade of each of the knives 14 b, 24b, and 34 b is small (e.g. about 0.05 to 0.1 mm), the blade itself isrelatively very sharply ground, a shearing force is applied to the fiberweb 1 due to the knives 14 b, 24 b, and 34 b, and as indicated by across-section A-A, the fiber web 1 is completely cut from a top surfaceto a bottom of the fiber web 1 in a thickness direction so that thesealing portion 2 b that is instantaneously sealed by heat can beformed.

However, if the thickness of the blade of each of the knives 14 b, 24 b,and 34 b is large (e.g. about 0.1 to 1 mm), then the blade itself isrelatively less sharply ground or as the usage period of the knives 14b, 24 b, and 34 b elapses, the blade becomes more dull, due to thepressure of the knives 14 b, 24 b, and 34 b, as indicated by across-section A′-A′. Thus, a gap between the cutting portions 2 a′ onthe top surface of the fiber web 1 is relatively large, and the sealingportion 2 b′ is not completely cut on the bottom of the fiber web 1.Rather, the sealing portion 2 b′ is connected to the bottom of the fiberweb 1 with a minimum thickness (e.g. at least about 0.16 to 0.2 mm), oreven in this case, the bottom of the sealing portion 2 b′ may becompletely cut and then may be sealed.

The sealing portions 2 b and 2 b′ emerge when a predetermined pressureis applied to the knives 14 b, 24 b, and 34 b, as do the cuttingportions 2 a and 2 a′.

According to various embodiments, the winding roll 16 may be rotatableby the rotation shaft 14 c and may be rotated by a driving unit, such asa motor.

Finally, the wound melt-blown fiber web 1 based on the desired shape ofthe final product.

FIG. 5B is a plan view and a cross-sectional view of a melt-blown fiberweb 1 according to another embodiment of the present invention. Whenstraight line-shaped or cross-shaped knives 14 b, 24 b, and 34 b arearranged at both corners of cutting and sealing units 15, 25, and 35,sealing portions 2 b are formed at the corners of the melt-blown fiberweb 1, as illustrated in FIG. 5B.

FIG. 6 is a plan view of a melt-blown fiber web that is cut inpredetermined patterns, according to an embodiment of the presentinvention.

The composition of the melt-blown fiber web 1 according to the presentinvention may be modified in various ways according to the desiredspecifications of the final product. For example, the melt-blown fiberweb 1 may include polyester, a staple fiber formed of olefin, andparticles, in addition to a melt-blown fiber so as to provide variousfunctions. Further, various types of surface protection layers, forexample, spunbonds, nylon films, and aluminum foils, may be used toprotect the surface of the melt-blown fiber web 1.

The shape of the knife 14 b and an interval between the knives 14 b thattreat the surface of the melt-blown fiber web 1, may be freely adjustedaccording to a target property of the final fiber web 1.

Thus, according to the present invention, portions of the melt-blownfiber web 1 are cut and sealed by applying a shearing force to thesurface of the melt-blown fiber web 1 using the rolling roll 14 or thepress mold 24 having a surface on which the knives 14 b are provided.The knives 14 b may be provided to have a predetermined shape and mayfurther be arranged at predetermined intervals. AS such, theconcentration force and elasticity of the melt-blown fiber web 1 can beeasily improved without degrading the inherent function of the fiber web1.

Hereinafter, the present invention will be described based on thefollowing examples; however, aspects of the present invention are notlimited thereto.

Embodiment 1

A melt-blown fiber web was manufactured according to the presentinvention by using the same method as the process of manufacturing themelt-blown fiber web of FIG. 1. Detailed manufacturing conditions are asbelow.

A melt-blown fiber having a weight of 200 g/m², in which 20 wt % of astaple fiber formed of polypropylene and having an average thickness of6 denia and an average length of 40 mm, of which a surface was treatedwith a silicon emulsifier, was randomly mixed with 80 wt % of amelt-blown microfiber formed of polypropylene and having an averagethickness of 3 μm, and was manufactured using a vertical melt-blownmanufacturing apparatus. The manufactured melt-blown fiber web was woundto a width of 1,800 mm and a length of 50 m.

Both sides of the wound melt-blown fiber web were combined with aspunbond nonwoven fabric having the weight of 15 g/m² so as tomanufacture a melt-blown fiber web having a total weight of 230 g/m² anda thickness of 13 mm.

After the melt-blown fiber web that was wound with the width of 1,800 mmand the length of 50 m was positioned in a state in which the melt-blownfiber web was wound on the unwinder 10, as illustrated in FIG. 2, themelt-blown fiber web was put on a transfer unit having a width of 2,100mm and a length of 3 m and was transferred.

The speed of the transfer unit was 5 m per minute. The transferredmelt-blown fiber web was allowed to be passed through the rolling roll14 having a length of 2,000 mm in which cross-shaped knives 14 b(thickness: 0.7 mm/height: 8 mm) having a width of 15 mm and a length of10 mm were arranged at an interval of 20 mm, thereby cutting andthermally sealing the surface of the melt-blown fiber web.

COMPARATIVE EXAMPLE

Samples were extracted from a conventional melt-blown fiber web not inaccordance with the present invention. In particular, a conventionalmelt-blown fiber comprises a mixing part, wherein a resin compositionconsisting of thermoplastic resin, an antioxidant, a heat stabilizer,etc., are mixed; a drying part, wherein the water contained in thethermoplastic resin composition supplied from the mixing part is removedby drying before it is inputted into a heat extrusion part; a heatextrusion part, wherein the thermoplastic resin composition suppliedfrom the drying part is subjected to heating, milling, melting, andextrusion; a melt-blown fiber radiating part, wherein the thermoplasticresin composition supplied from the heat extrusion part radiates fibersin the form of a filament(ultrafine fiber); a gas injection part,wherein a gas whose injection speed and injection amount are variedrandomly and continuously, is radiated into the melt-blown fiber beingradiated from the melt-blown fiber radiating part; a collection part,wherein the melt-blown fiber is collected and forms a melt-blown fiberweb; and a winding part, wherein the fiber well formed in the collectionpart is wound. That is, the melt-blown fiber refers to a fiber formed byextrusion of a melted processable polymer via a plurality of minutecapillary tubes along with a compressed gas under high temperature andhigh pressure. Here, the capillary tubes may be provided in variousforms including a tube with a circular cross-section, a tube with apolygonal cross-section including triangular, and tetragonal shape, anda tube with a star shape. It is noted that the compressed gas under hightemperature and high pressure enables a reduction in the diameter of thefiber of a melted thermoplastic polymer material to about 0.3 to about10 μm. The melt-blown fiber may be a continuous or discontinuous fiber.

EXPERIMENTAL EXAMPLE

The effect of the melt-blown fiber web manufactured according toEmbodiment 1 of the present invention was demonstrated by changingexperimental conditions, and experimental results thereof are asfollows.

The thickness of a sample manufactured by the method according toEmbodiment 1 was measured using the following method.

After five samples having the shape of a square having the size of 100mm×100 mm were extracted from arbitrary places of the melt-blown fiberweb based on an international thickness measurement standard ISO 5084, acircular pressurization plate having a diameter of 100 mm was placed onthe five samples so that a total sum of pressure applied to the fivesamples was 0.1 kPa. The thickness of each sample was then measuredusing vernier calipers, and an average value thereof was indicated as arepresentative value.

Thickness measurements after the samples were pressurized, were carriedout in such a way that five samples having the shape of a square havingthe size of 100 mm×100 mm were extracted from arbitrary places of themelt-blown fiber web, a pressurization plate having the weight of 1 kgand the size of 120 mm×120 mm was put on the five samples, was left for24 hours in a state in which humidity was 50% and temperature was keptat 25° C. After 2 hours elapses from time when the pressurization platewas removed, the thickness of each sample was measured using verniercalipers, and an average value thereof was indicated as a representativevalue.

A test for the concentration force of the samples was carried out insuch a way that both surfaces of the fiber web were pulled out at aspeed of 25 mm per minute based on GMW 14695 so as to measure a maximumload in which concentration was destroyed. Absorption performance ofsamples having the size of 1,000 mm×1,200 mm was tested using areverberant chamber in which the samples were placed, based on atechnical standard GM 141777, and test results thereof are shown in thefollowing Table 4.

TABLE 1 Concentration destruction strength of fiber web Concentrationdestruction strength Embodiment 1 51 N/cm² Comparative example 1 40N/cm²

TABLE 2 Thickness of fiber web before pressurization ThicknessEmbodiment 1 13 mm Comparative example 1 13 mm

TABLE 3 Thickness of fiber web after pressurization Thickness Embodiment1 13 mm Comparative example 1 13 mm

TABLE 4 Absorption performance 400 500 630 800 1k 1.25k 1.6k 2k 2.5k3.15k 4k 5k 6.3k 8k 10k Embodiment 1 0.32 0.35 0.51 0.62 0.80 0.86 0.870.93 0.99 0.98 0.97 0.91 0.87 0.86 1.06 Comparative 0.32 0.36 0.51 0.610.80 0.86 0.88 0.93 0.98 0.98 0.97 0.90 0.88 0.86 1.06 example 1

As illustrated in FIG. 8, as a result of testing, the fiber webaccording to the present invention, of which a surface was cut andsealed at predetermined intervals, demonstrated almost the sameabsorption performance as the comparative example.

The thickness of the fiber web was the same in Embodiment 1 and thecomparative example. The thickness of the fiber web after pressurizationwas restored by 100% in Embodiment 1, whereas, in the comparativeexample, about 8% of a thickness loss occurred.

Also, concentration destruction strength of Embodiment 1 was increasedby about 28% compared to the comparative example.

After considering all test results, in the melt-blown fiber web that wasmanufactured according to the present invention, elasticity andconcentration force was improved without degrading the inherentcharacteristics of the fiber web, such as absorption performance.

As described above, the advantages of a melt-blown fiber web withimproved concentration force and elasticity and a method and apparatusfor manufacturing the melt-blown fiber web are as follows.

Firstly, a plurality of cutting portions and a plurality of sealingportions are formed in predetermined patterns on the surface of themelt-blown fiber web so that a concentration force between microfibersthat form the melt-blown fiber web can be increased and a melt-blownfiber web with reinforced concentration force can be manufactured.

Secondly, the elasticity of the melt-blown fiber web can be improved bythe plurality of cutting portions and the plurality of sealing portionsthat are formed in the predetermined patterns on the melt-blown fiberweb.

Thirdly, patterns and shapes of the cutting portions and the sealingportions formed on the melt-blown fiber web may be varied so that theconcentration force and elasticity of the fiber web can be tailored tomanufacture a desired melt-blown fiber web.

While the present invention has been particularly shown and describedwith reference to exemplary embodiments thereof, it will be understoodby those of ordinary skill in the art that various changes in form anddetails may be made therein without departing from the spirit and scopeof the present invention as defined by the following claims.

1.-4. (canceled)
 5. An apparatus for manufacturing a melt-blown fiberweb with improved concentration force and elasticity using athermoplastic resin, the apparatus comprising: an unwinder that unwindsa predetermined amount of a wound melt-blown fiber web a transfer unitthat transfers the melt-blown fiber web unwound by the unwinder; acutting and sealing unit that cuts and fuses a surface of thetransferred melt-blown fiber web in predetermined patterns; and awinding roll that winds the melt-blown fiber web.
 6. The apparatus ofclaim 5, wherein the cutting and sealing unit comprises a rolling rollhaving an outer circumferential surface, a plurality of knives having apredetermined shape that are arranged at predetermined intervals on theouter circumferential surface of the cutting and sealing unit, whereinrotation of the knives pressurizes the surface of the melt-blown fiberweb at predetermined intervals thereby cutting and sealing themelt-blown fiber web.
 7. The apparatus of claim 5, wherein the cuttingand sealing unit comprises a press mold that has knives having apredetermined shape arranged at predetermined intervals on a bottomsurface of the cutting and sealing unit, the knives being verticallymovable, wherein vertical movement of the knives pressurizes the surfaceof the melt-blown fiber web at predetermined intervals thereby cuttingand sealing the melt-blown fiber web.
 8. The apparatus of claim 5,wherein the cutting and sealing unit comprises a press mold that hasknives having a predetermined shape arranged at predetermined intervalson a bottom surface of the cutting and sealing unit and a steel plate asa support plate, the knives being vertically movable, wherein verticalmovement of the knives pressurizes the surface of the melt-blown fiberweb at predetermined intervals using the steel plate thereby cutting andsealing the melt-blown fiber web.
 9. The apparatus of claim 6, wherein,when the knives form cutting portions and sealing portions on themelt-blown fiber web, the sealing portions are completely cut and sealedby a shearing force of the knives based on a thickness of a blade ofeach of the knives, or the sealing portions are cut with a minimumthickness of about 0.16 to 0.2 mm due to pressure of the knives and thenare sealed.